Understanding DNA repair pathways, and how deficiencies in these pathways cause human disease requires the elucidation of a series of very complex events, including:
Identifying the constituents of multi-protein complexes
Characterising protein–protein interactions
Determining protein localisations and post-translational modifications
Reconstituting functional activity from purified components in vitro.
To comprehend these complex events we are focusing on three principle areas of research:
1. Understanding the mechanism and regulation of DNA double strand break repair
Currently we are attempting to identify and characterise how the various proteins that make up the DNA resection machinery contribute to the repair of one of the most toxic lesions that cells can suffer i.e. DNA double strand breaks (DSBs). Our lab uses high-throughput technologies, including genomic-proteomic pipelines combined with mass spectrometry-based analysis, bioinformatics and real time live cell imaging. The identification of novel co-factors that cooperate with the resection machinery to promote DSB repair could aid the development of novel treatment strategies to combat cancer and other hereditary disorders.
2. Investigating the molecular mechanisms of cellular responses to replicative stress
The ability of cells to divide allows organisms to grow and reproduce. This process requires copying and maintaining a vast amount of genetic information. Therefore, accurate replication of DNA is essential not only for the preservation of genomic integrity but also the continuation of life. To accomplish this, cells have evolved complex mechanisms to both replicate cellular DNA with high fidelity and to preserve its integrity.
Nevertheless, genomic integrity is challenged during every cell cycle by lesions present in the DNA template that can collapse the replication machinery, contributing to tumour progression by driving chromosomal instability. Our goal is to understand cellular strategies that prevent replication perturbation and mechanisms by which cells accomplish genome duplication under conditions of replicative stress. Ultimately, we want to use this information for the implementation of novel cancer treatment options.
3. Understanding the DNA repair mechanisms disrupted in the childhood cancer predisposing syndrome Fanconi anemia
Children afflicted with Fanconi anemia (FA) show developmental defects, progressive bone marrow failure and have up to 1000-fold increased risk of cancer. The genes mutated in this syndrome encode a network of ‘caretaker’ proteins, which not only ensure that DNA is accurately copied but also prevent replication failure and associated genomic instability. Consequently, a properly functioning FA pathway is important for normal development, haematopoiesis and suppression of solid tumours in everyone. This underscores the essential role of this pathway in suppressing tumour formation.
We are particularly interested in understanding how the FA proteins function to promote genome stability, and whether dysfunctional replication-mediated DNA repair is a common signal that drives FA disease progression to leukaemia. A long-term goal of our research is to elucidate the FA-dependent mechanism required to suppress the devastating haematological and malignant conditions associated with FA and use this information for the development of novel treatment options for FA sufferers.